Supermarket secrets and a new study that proves something you may have thought you knew already. You shouldn't shop hungry. Abc's abbie boudreau put this to the test and here's what she found out. Reporter: It can be a dangerous place, the grocery store on an empty stomach. &#9834; and if you're anything like me we head straight to the carbs. Mm-mm. I can plow through a whole bag of these in an hour, I swear. A study just released confirms what most figured, hungry shoppers choose on average 23% more processed junk food than shoppers on a full belly. Researchers at cornell university took 68 participants, half went shopping on an empty stomach. The other half were given wheat thins. The study found the shoppers who were hungry bought higher calorie foods. We're more likely to reach foods that are convenient, not just at that point in time but continue to reach for them throughout the week because that's what we're bringing into the house. Reporter: In our not so scientific study I went snack-free for four hours and as this busy mom of two young boys to do the same. How are you feeling? I am feeling so hungry my brain is like freezing. Reporter: What she didn't know like the real study i munched on wheat thins to see if that would help me make healthier choices but what will she do. I'll rip the bags open and start eating when I put them in the shopping cart. 20 minutes later. What do you think about some of your food choices when you in your cart? I'm hungry. You're like give me those cheetos. Reporter: She not only chose higher calorie foods but a lot of it. Here's my cart. A little healthier but I wasn't as hungry I got the chicken and veggies. Time to confess my preshopping secret snack. So I had a bunch of wheat thins before I went shopping. Oh, that's not fair. You cheated. Reporter: So what's the moral of this snacking snafu? It's really pretty simple. Don't leave home without a box of these. For "good morning america," abbie boudreau, abc news, los angeles.

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